Over three millions U.S. adolescents are affected by chronic diseases that they will need to manage as they enter adulthood. Online disease self-management (ODSM) systems may be of great value in this population because these systems provide adolescents with a user-friendly mechanism for tracking symptoms, medications, and health behaviors. Little is known, however, about the factors associated with adolescent ability or willingness to use such tools. In particular, little is known about health literacy in adolescents or about how limitations in health literacy may inhibit use of online disease self-management. The long term goal of our research program is to improve health care for adolescents through expanded use of health care informatics. In this project, we will combine state of the art research in health literacy and technology acceptance to accomplish the following aims: (1) To assess health literacy in a population of adolescents treated for asthma or diabetes and to assess variation in these measures across racial/ethnic and income characteristics and (2) To test an extension of the Unified Technology Acceptance and Utilization Theory predicting behavioral intention to use and actual use of ODSM systems based on individuals'health literacy, computer self-efficacy, health self-efficacy, technology expectancies, computer access, and sociodemograhic variables. In this study, randomly selected adolescents, ages 13-18, receiving care in hospital based pediatric specialty clinics will be assessed for general, health, and computer literacy and attitudes and intentions toward online disease management support, and access to computers and the internet. They will also receive brief education on online disease self-management. Ninety-day follow-up calls will assess whether youth attempted use an ODSM system and assess satisfaction and barriers. Findings from this study will expand knowledge of adolescent health literacy and will provide a framework for developing and promoting e-health use which could ultimately improve adolescent health behaviors and health status. Public Health Relevance: Over three million U.S teens are affected by chronic diseases and these youth must be prepared to manage these conditions themselves as they reach adulthood. Online disease self-management systems can play an important role in assisting with this challenging transition. This study will assess health literacy in adolescents and will explore how health literacy along with computer self-efficacy, health self-efficacy, health related quality of life, technology expectancies, computer access, and sociodemographic factors impact willingness to use online disease management systems.